Pressure cooker closure



Oct. 14, 1947. M. J. ZIMMER PRESSURE COOKER CLOSURE 2 Sheets-Sheet l Filed Feb. 12, 1945 ill WI 1 INVENTOR Myxao/v J. 2/! s2 ATTORNEY Oct. 14, 1947, ZIMMER I 2,429,151

PRESSURE COOKER CLOSURE Filed. Feb. 12,, 1946 2 Sheet-Sheet 2 g S 23 37 I 29 as as 39: l '26 I9 I L--- J \Q Ii I 4/ 20 I v l4 FIG. .3

3a 4 v a; 2

FIG. 4.

. INVENTOR. MYQON J ZIMMER Patented Oct. 14, 1947 Myron J. Zimmer, Wood Dale, 111., assignor to Ekco Products Company, Chicago, 111., a corporation of Illinois Application February 12, 1946, Serial No. 647,157 7 Claims. (01. 220-55) This invention relates to closures for pressure cookers of the type wherein the rim of the closure is upwardly engageable with a downwardly facing seating surface within the cooker body. In this type of cooker, the closure is supported at its center by a stem in upright relation to the outer surface of the closure and an overhead member adapted to rest on shoulders outside the cooker body across the mouth of the cooker, there being a bearing on the overhead member in which the stem is shiftable downwardly from a position wherein the rim of the closure is in engagement with the seating surface within the cooker body to space the closure and overhead member at such distance apart as to obtain clearance needed for moving the closure through the mouth of the cooker body toward and away from a position in which the closure is below said seatin surface.

Wearing of the parts due to severe usage may cause variations in the travel of the stem as well as damage to the cooperating seal-producing surfaces of the closure and cooker body, with the result that steam escapes around the edge of the closure. The same condition may occur if the parts are inaccurately manufactured or if a gasket placed between the seal-producing surfaces is ineffective in producing the desiredseal.

The present invention accordingly contemplates the provision of means to insure tight sealing engagement of the closure with the cooker body to compensate for wear or inaccuracies in the parts.

More specifically, this invention provides means of this character, including a pressure applying member movably carried by the overhead supporting member and having a camming relation with the stem to apply an upward pulling force on the stem whereby a sealing engagement between the rim of the closure and the seating surface within the cooker body is positively attained.

With the above objects in view, as will be apparent, this invention consists in the construction, combination and arrangement of parts, all as hereinafter more fully described, claimed and illustrated in the accompanying drawings, wherein:

Fig. 1 is a side elevational view of a pressure cooker constructed in accordance with this invention, with parts removed and in section, and showing the closure in seated position.

Fig. 2 is an enlarged fragmentary vertical sectional View taken on line 22 of Fig. 1.

Figs. 3 and 4 are views similar to but each taken on a vertical plane at 90 degree variance to the plane of the sectional View in Fig. 2 and showing the relative positions of the cover rim and the seat with which it is engageable, when the control means'for effecting positive sealing action therebetween is in inoperative and operative positions, respectively. I

Reference being had more particularly to the drawing, l0 generally represents a receptacle of suitable shape and capacity, having a bottom wall II and an upright side wall l2 terminating at its upper edge in an inwardly projecting lip or flange forming the periphery 13 of the mouth of the receptacle. The periphery I3 is non-circular soas to provide a mouth or opening at the top of the receptacle having a-maximum transverse dimension at substantially right angles to its minimum transverse dimension.

The closure indicated generally by the refer: ence numeral l4 comprises a disk-like member of such dimension and shape as to provide a peripheral rim l5 adapted to underlie a downwardly facing seating surface It formed by the underside of the flange or lip projecting inward ly from the upper edge of the receptacle side wall l2 and of smaller minimum transverse dimension than the maximum transverse dimension of the mouth. Rim I5 supports a gasket ll of such material as to readily form a sealing engagement with the seating surface It and yet easily detachable therefrom when it is desired to remove the closure from the receptacle. An overhead member l9, seated as at 20 and 2| on shoulders outside the receptacle II] at opposite sides of the mouth of the receptacle, is provided with a bearing 22 in which a cylindrical stem 23, fixed to the center of the closure i4 and projecting axially upwardly therefrom, is rotatable about its upright axis and is 'shiftable downwardly of the member l9 from a position wherein the closure is in sealing engagement with the seating surface I6 (as shown in Fig. 4) to a substantially lowered position (as indicated'in the dotted line portion of Fig. 3). In the latter po-- sition, the closure and the overhead member I9 are spaced a distance apart compatible with the clearance required therebetween to move the.

closure through the opening or mouth of the receptacle toward and away from a position within the receptacle. The upper end of the stem 23 is provided with an operating knob or handle" preferably in the form of an inverted metal cap 24 having its outer surface covered by a shell 25 of suitable heat insulating material, such as Bakelite, fixed to the stem 23 by means of a screw 26. The cap 24 is conveniently joined to the stem 23 by having the edges of an opening in its base crimped to the upper end of the stem as shown in Figs. 3 and 4. The portion of the stem located above the bearing 22 is embraced by a coil spring 21. One end of the spring bears against the inner surface of the cap 24 and the opposite end of the spring reacts against a ring 28 confined against the base of a ferrule 29 formed integrally with and extending axially upwardly and outwardly from the bearing 22 in the supporting member I9. As will be observed from Figs. 3 and 4, the upper peripheral edge portion 30 of the ferrule 29 is such that it is overlapped by the lower side wall portion 3| of the operating knob 24 when the stem 23 and knob 24 are in upwardmost relation to the ferrule. Consequently a horizontal shoulder 32 29. formed in the upper portion of the ferrule 29 and extending circumferentially through an arc of approximately 90 degrees is engageable by a shoulder 33 in the cap 24 to lock the stem 23 in a position in lowermost relation to the supporting member l9 when the operating knob is depressed against the action of the spring 21 and rotated through an arc of 90 degrees from an initial position as shown in Figs. 3 or 4 to a position as shown in Fig. 2. When positioned as shown in Fig. 2, the closure may be tilted and lifted from the receptacle lengthwise of its longest axis, during which process the supporting member 19 is removed from the seats 29 and 2!. In order to provide clearance for the shoulders 32 and 33 to accommodate movement of the ferrule and cap toward and away from interlocked position, the ferrule is formed with an axially depressed portion 34 in which the shoulder 33 in the cap 24 has guided movement in a fixed axial path.

As shown in Fig. 3, the spring 27 preferably exerts a force only slightly in excess of the weight of the stem 23 and the parts held thereby, including the closure, so as to assure a relatively sensitive direct manual control of the stem. For this reason the spring 2'! is not sufficiently strong to lift the gasket l1 into pressure-sealed engagement with the seating surface within the receptacle in the event of any irregularit in the contour of the cooperating sealing surfaces of the closure and the receptacle, or slight variations in the seating of the supporting member at 2| and 20.

In order to provide positive sealing action between the closure rim and the cooperating surface portions of the receptacle by means adapted to exert an axial upward pull on the stem and closure in excess of the force available through the spring 21, the present invention contemplates control means comprising a slide mounted on the supporting member movable into interlocking engagement with the stem. As shown in Figs. 3 and 4, the slide comprises a knob 35 adapted to slide on the upper surface of the member I9 and to straddle the longitudinal edges 35 of an elongated slot formed in and extending lengthwise of said member I9, from which a vertical leg 31 of a pin projects downwardly for insertion through the slot aforesaid and a horizontal leg 38 extends radially inwardly from said vertical leg 31 and is supported below the member IQ for longitudinal sliding movement of the leg 38 through a bearing 39 on the underside of the member IS. The inward end of the leg 38 is rounded to provide a nose adapted to enter a transverse bore 49 in the stem. As shown in the drawings the bore 40 presents an upper surface slanting downward in the direction of stem- Ward movement of the leg 38 so as to be gradually lifted as the nose of the leg 38 is moved toward the position shown in Fig. 4. In this position the stem 23 is locked against rotation as Well as against downwardmovement whereby accidental depression of the operating knob is effectively avoided. When it is desired to remove the closure, the control slide knob 35 is moved backward or into the position shown in Fig. 3 so as to free the stem for depression and rotation of, the closure for disposal in such relation to the widest axis of the receptacle mouth as to permit the edges of the closure rim to pass between the side edges of the receptacle mouth. 3 It is obvious that various changes and modifications. may be made in the details of construction and design of the above specifically described embodiment of this invention without departing from the spirit thereof, such changes and modifications being restricted only by the scope of the following claims.

What is claimed is:

1. The combination of a receptacle having a mouth of non-circular contour, a downwardly facing seating surface within the receptacle and located peripherally of said mouth, a closure therefor of smaller minimum transverse dimension than the maximum transverse dimension of said mouth and having a rim adapted to underlie and have pressure sealed engagement with said seating surface, a stem fixed to the center of the closure and projecting axially upwardly therefrom, an overhead support cooperating with the receptacle to occupy a selected position across said mouth, means on said supporting member providing a bearing in which said stem is slidable axially, means for adjusting the stem axially toward and away from a position wherein the rim of the closure is in pressure sealing engagement with said seating surface including a control member slidably mounted on the supporting member for lineal movement transversely of the path of travel of the stem and means on the stem with which said control member is engageable in one direction of its movement to .lock said stem against movement away from a position wherein the rim of the closure is in pressure sealing engagement with said seating surface.

2. The combination as defined in claim 1 wherein the stem is rotatable in said bearing in which the stem is slidable axially.

3. The combination of a receptacle having a mouth of non-circular contour, a downwardly facing seating surface within the receptacle and located peripherally of said mouth, a closure therefor of smaller minimum transverse dimension than the maximum transverse dimension of said mouth and having a rim adapted to underlie and have pressure sealed engagement with said seating surface, a stem fixed to the center of the closure and projecting axially upwardly therefrom, an overhead support cooperating with the receptacle to occupy a selected position across said mouth, means on said supporting member providing a bearing in which said stem is slidable axially, means for adjusting the stem axially toward and away from a position wherein the rim of the closure is in pressure sealing engagement with said seating surface including a control member slidably mounted on the supporting member for lineal movement transversely of the path of travel of the stem and a transverse bore in the stem presenting an upper surface slanting downward in the direction of stemward movement of said control member with which the latter is engageable in one direction of its movement to lock said stem against movement away from a position wherein the rim of the closure is in pressure sealing engagement with said seating surface.

4. The combination of a receptacle having a mouth of non-circular contour, a downwardly facing seating surface within the receptacle and located peripherally of said mouth, a closure therefor of smaller minimum transverse dimension than the maximum transverse dimension of said mouth and having a rim adapted to underlie and have pressure sealed engagement with said seating surface, a stem fixed to the center of the closure and projecting axially upwardly therefrom, an overhead support cooperating with the receptacle to occupy a selected position across said mouth, means on said supporting member providing a bearing in which said stem is slidable axially, means for adjusting the stem axially toward and away from a position wherein the rim of the closure is in pressure sealing engagement with said seating surface including a control member slidably mounted on the supporting member for lineal movement transversely of the path of travel of the stem and means on the stem with which said control member is engageable in one direction of its movement to lock said stem against movement away from a position wherein the rim of the closure is in pressure sealing engagement with said seating surface and a spring acting between said stem and said supporting member operative to urge said stem toward a position wherein the rim of the closure is in pressure sealing engagement with said seating surface.

5. The combination of a receptacle having a mouth of non-circular contour, a downwardly facing seating surface within the receptacle and located peripherally of said mouth, a closure therefor of smaller minimum transverse dimension than the maximum transverse dimension of said mouth and having a rim adapted to underlie and have pressure sealed engagement with said seating surface, a stem fixed to the center of the closure and projecting axially upwardly therefrom, an overhead support cooperating with the receptacle to occupy a selected position across said mouth, means on said supporting member providing a bearing in which said stem is slidable axially, an elongated slot in and extending lengthwise of said supporting member, a knob adapted to slide on the upper surfaceof said supporting member and to straddle the longitudinal edges of said slot, means for adjusting the stem axially toward and away from a position wherein the rim of the closure is in pressure sealing engagement with said seating surface including a pin having a vertical leg fastened to said knob and projecting downwardly therefrom and through said slot and a leg extending radially inwardly from said vertical leg and supported inwardly of the supporting member for lineal shifting movement toward and away from a position across the path of travel of the stem, and a transverse bore in said stem with which the inward end of said latter leg of the pin is engageable in one direction of its movement to lock the stem against movement away from a position wherein the rim of the closure is in pressure sealing engagement with said seating surface.

6. The combination of a receptacle having a mouth of non-circular contour, a downwardly facing seating surface within the receptacle and located peripherally of said mouth, a closure therefor of smaller minimum transverse dimensions than the maximum transverse dimension of said mouth and having a rim adapted to underlie and have pressure sealed engagement with said seating surface, a stem fixed to the center of the closure and projecting axially upward therefrom, an overhead support cooperating with the receptacle to occupy a selected position across said mouth, means on said supporting member providing a bearing in which said stem is slidable axially, means for adjusting the stem axially to move the rim of the closure int engagement with said seating surface, and a pressure applying member movably carried by said supporting member and engageable with said stem independently of said stem adjusting means to effect further axial movement of said stem and thereby force said rim into pressuresealing relation with said seating surface.

7. The combination of a, receptacle having a mouth of non-circular contour, a downwardly facing seating surface within the receptacle and located peripherally of said mouth, a closure therefor of smaller minimum transverse dimensions than the maximum transverse dimension of said mouth and having a rim adapted to underlie and have pressure sealed engagement with said seating surface, a stem fixed to the center of the closure and projecting axially upward therefrom, an overhead support cooperating with the receptacle to occupy a selected position across said mouth, means on said sup-- porting member providing a bearing in which said stem is slidable axially, means for adjusting the stem axially to move the rim of the closure into engagement with said seating surface, and a pressure applying member carried by said supporting member independently of said stem adjusting means, and having a camming engagement with said stem to eifect further axial movement of said stem and thereby force said rim into pressure-sealing relation with said seating surface.

MYRON J. ZIMME'R.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,759,732 Charlot May 20, 1930 1,683,102 Sanftleben Sept. 4, 1928 

